As we increase our understanding of serotonin 2a receptor agonist effects on the default mode network and consciousness, we must also compare "psychedelic glossolalia" with traditional "speaking in tongues." Here is Wikipedia's review of glossolalia.

This blog post is an introduction to the subject and will be updated over the next few weeks.

Terence McKenna mentions glossolalia in his theory of human brain development and consciousness.

McKenna does a normal waking consciousness rendition of glossolalia in this video.